Cooled Irrigation in PPV Better for Patients With Pseudophakia and Gas Tamponade

Cooled irrigation may be more advantageous for corneal parameters in patients with psuedophakia and gas tamponade, according to findings published in Eye & Contact Lens. Researchers conducted a prospective, randomized study to compare the effects of cooled and room temperature irrigation on the preoperative and early postoperative corneal endothelial parameter values in posterior vitrectomy.

The study included 2 groups totaling 68 patients who underwent a standard 3-port, 23 gauge posterior vitrectomy operation by a single surgeon. Group 1 included 36 patients who received cooled irrigation solution during surgery, and group 2 consisted of 32 patients who received room temperature irrigation solution during surgery. Four groups within the 2 study groups were created according to their history of noncomplicated cataract surgery (phakic or pseudophakic) and the types of tamponade used (silicon or gas). Researchers compared the central corneal thickness (CCT), endothelial cell density (ECD), mean cell area (MCA), hexagonal cell percent, and coefficient of variation of cell area (CV) parameter values of the groups 1 month pre and postoperatively.

The study found no statistically significant differences between the pre and postoperative corneal parameter values in either the cooled irrigation or room temperature irrigation groups (P >.05). However, the percentage of preoperative-postoperative change in all corneal parameter values was higher in group 2. Also, the negative effects of gas tamponade in the pseudophakic group were significantly higher in the postoperative values for the ECD, MCA, CV, and CCT parameters compared with the preoperative values (P <.05).

The researchers explained that, although some studies have investigated the effect of the temperature of the irrigation solution used in cataract surgery on the endothelial parameter values, this study is the first to examine the effect of the temperature of the irrigation solution used for pars plana vitrectomy on endothelial parameter values.

The study also notes that its identification of the corneal benefits of cold irrigation in patients with pseudophakia gas tamponade has clinically useful implications.

“Specular microscopic evaluation should be performed preoperatively, especially for pseudophakic patients, and the use of refrigerated irrigation solutions should be evaluated according to the status of endothelial cells,” the researchers explain.

Study limitations include small sample size, short follow up period, and possible confounding of results given different photocoagulation times for each patient.